Torpedo propeller guard-lock



Jan. 1, 1957 E. R. HESS 2,775,949

TORPEDO PROPELLER GUARD-LOCK Filed June 50, 1955 2 Sheets-Sheet l 1460M A ($1M Jan. 1, 1957 E. R. HESS 2,775,949

' TORPEDO PROPELLER GUARD-LOCK Filed June 30, 1955 2 Sheets-Sheet 2 IN VEN TOR.

1'9 Z, .EDWARD R. HESS F fl/zwkfliw 1 ATTOR N'E YS TORPEDO PROPELLER GUARD-LOCK Edward R. Hess, Sharon, Pa., assignor, by mesne assignments, to the United States of America as represented by the Secretary of the Navy Application June 30, 1955, Serial No. 519,297

6 Claims. (Cl. 114--20) This invention relates to torpedoes and more particularly to improvements in protecting and locking apparatus for torpedo propellers.

Underwater torpedoes are conventionally provided with a single propulsion propeller at their rear ends or tandem propellers which rotate in opposite directions. Except forcertain types of torpedoes having shrouded propellers, the propeller or propellers are normally unprotected against damage during handling operations and, in event the propulsion system should prematurely start operation, present a hazard to personnel. To obviate the hazard, aforesaid, on counter-rotating propeller torpedoes, it has been conventional practice to lock the propellers together by a suitable bar-like member extending therebetween. Another expedient employed is a cylindrical can-shaped shroud, removably disposed around the propellers. With this construction the propellers are protected against damage during handling and it also protects personnel from injury to a considerable extent in event the propulsion system operates prematurely. The propellers rotate, however, within the shroud upon premature operation and do not afford complete protection against injury.

One of the objects of this invention is to provide an improved form of torpedo propeller protecting device in which a propeller is not only protected against handling damage but also positively constrained against rotation when the device is attached to a torpedo, thereby afiording complete protection against injury to personnel.

Another object is to provide a device of the foregoing type which may be employed with torpedoes having single or tandem propellers.

Other objects are to provide a device of the type referred to which is light in weight yet inherently strong and economical of fabrication.

Further objects, advantages and salient features will become more apparent from the description to follow, the appended claims and the accompanying drawing in which:

Fig. 1 is a front elevation of the invention as viewed in the direction of arrow 1, Fig. 2, portions of a torpedo being shown by dotted lines,

Fig. 2 is a side elevation as viewed in the direction of arrow 2, Fig. 1, and

Fig. 3 is fragmentary elevation as viewed in the direction of arrow 3, Fig. 2.

Referring in detail to the drawing, which illustrates one form of the invention which may be employed with a torpedo having a single two bladed propeller, tandem two bladed propellers or tandem four bladed propellers, the invention comprises, in general, a cruciform propeller guard and lock 10, hereinafter referred to asa guardlock, which is removably attached to the rear end of a torpedo T, shown in dotted lines, and which houses tandem propellers 11, 11a.

The guard-lock is provided with a cruciform rear end wall 12 of sheet metal having a central circular aperture 13 therein, this aperture being of a size to fit on propeller hub 14 to thus center and support the end wall in a predetermined position relative to the propeller blades. Sheet nited States Patent 2,775,949 .F ented .lam 1., 1 5

2 metal walls 15 are secured to. the outer ends of each; of the ar ess 6 o w ll 1 npernen a a on h p ther to; Walls .7 hav n u stantia ly h an ular di posed portions 18, 18 are secured at their rear edges to end wall 12 and at their outer edges to adjacent walls 15. As will be apparent, the walls, in the order described, provide closures at the rear of the torpedo blades, the tips of the blades and the generally radial edges of the blades. The four spaces within the closure, hereinafter referred to as pockets 19 are of such size to loosely receive the various propeller blades.

A pair of bifurcated two part brackets 20 are each secured at the rear end thereof to opposite walls 15 and the adjacent walls 17. The forward end of each bracket straddles a fixed stabilizing fin 21 and is retained in position thereon by a pin 22 which extends through an aperture in the fin. The two brackets and their associated pins thus retain the guard-lock on the torpedo.

The pins may be attached to their brackets by flexible members 23 to prevent loss thereof and any suitable retainers (not shown) such as cotter pins, snap rings, etc. may be employed with the pins to prevent their unauthorized removal from the brackets when disposed in their securing position.

The guard-lock is preferably constructed of high strength corrosion resistant aluminum alloy and is designed in strength such that it will withstand shearing of all propeller blades from their hub or hubs without failure. Its compactness in design renders it the first guardlock which will pass all snubbing lines and other handling equipment employed by the Navy without removal from the torpedo. It may be installed on the torpedo in a shore workshop and need not be removed until the torpedo is loaded in a submarine launching tube. It thus affords complete protection against propeller damage and personnel injury during the various handling operations wherein damage or injury usually occur.

While the illustrated invention comprises a guard-lock having four equi-angularly spaced pockets for the torpedo blades it will be apparent that any number of spaced pockets may be employed.

Obviously many modifications and variations of the present invention are possible in the light of the above teachings. It is therefore to be understood that Within the scope of the appended claims the invention may be practiced otherwise than specifically described.

What is claimed is:

l. A guard-lock for a torpedo having at least one multiblade propeller at its rear end, comprising; walls forming angularly spaced pockets for receiving and enclosing the blades and preventing personnel access thereto, the pockets being open at only their forward ends to permit installation of the guard-lock on the torpedo, and means for securing the guard-lock in a predetermined position on the torpedo, whereby the guard-lock prevents rotation of the propeller blades.

2. A guard-lock in accordance with claim 1 wherein the last named means is adapted to engage at least two fixed fins on the topedo.

3. A guard-lock in accordance with claim 2 wherein said last named means includes a portion of the guard-lock adapted to engage a propeller hub.

4. A guard-lock for a torpedo having at least one multiblade propeller at its rear end, comprising a rear wall formed of equiangularly spaced outwardly extending portions, end walls extending forwardly from the outer ends of the outwardly extending portions, side walls extending forwardly from side edges of said portions and joined to the end walls, the rear wall, end walls and side walls forming equi-angularly spaced pockets open only at their forward ends, whereby the guard-lock may be disposed on the torpedo with the blades disposed within the pockets,

6. A guard-lock in accordance with claim 5 wherein said means comprises a pair of oppositely disposed bifurcated brackets extending forwardly from the pockets, their forward ends adapted to straddle oppositely disposed fixed fins in the torpedo, and means for securing said forward ends to the fixed fins.

No references cited. 

